test/test_iolib.py

#! /usr/bin/env python
#
# This file is part of pySerial - Cross platform serial port support for Python
# (C) 2001-2015 Chris Liechti <cliechti@gmx.net>
#
# SPDX-License-Identifier:    BSD-3-Clause
"""\
Some tests for the serial module.
Part of pyserial (http://pyserial.sf.net)  (C)2001-2009 cliechti@gmx.net

Intended to be run on different platforms, to ensure portability of
the code.

This modules contains test for the interaction between Serial and the io
library. This only works on Python 2.6+ that introduced the io library.

For all these tests a simple hardware is required.
Loopback HW adapter:
Shortcut these pin pairs:
 TX  <-> RX
 RTS <-> CTS
 DTR <-> DSR

On a 9 pole DSUB these are the pins (2-3) (4-6) (7-8)
"""

import io
import sys
import unittest
import serial

# trick to make that this test run under 2.6 and 3.x without modification.
# problem is, io library on 2.6 does NOT accept type 'str' and 3.x doesn't
# like u'nicode' strings with the prefix and it is not providing an unicode
# function ('str' is now what 'unicode' used to be)
if sys.version_info >= (3, 0):
    def unicode(x):
        return x


# on which port should the tests be performed:
PORT = 0


class Test_SerialAndIO(unittest.TestCase):

    def setUp(self):
        self.s = serial.serial_for_url(PORT, timeout=1)
        #~ self.io = io.TextIOWrapper(self.s)
        self.io = io.TextIOWrapper(io.BufferedRWPair(self.s, self.s))

    def tearDown(self):
        self.s.close()

    def test_hello_raw(self):
        self.io.write(b"hello\n".decode('utf-8'))
        self.io.flush()  # it is buffering. required to get the data out
        hello = self.io.readline()
        self.assertEqual(hello, b"hello\n".decode('utf-8'))

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
if __name__ == '__main__':
    import sys
    sys.stdout.write(__doc__)
    if len(sys.argv) > 1:
        PORT = sys.argv[1]
    sys.stdout.write("Testing port: %r\n" % PORT)
    sys.argv[1:] = ['-v']
    # When this module is executed from the command-line, it runs all its tests
    unittest.main()